OpenCV視頻處理教程問題

Question

我遵循iOS video processing tutorial on the OpenCV site並設法編譯並將其安裝在設備上。但是當我點擊「開始」按鈕時，沒有任何可見的情況發生。顯然，我的- (void)processImage:(Mat&)image回調從未被調用過。你能給我一些提示，可能是什麼問題？

有些事情我檢查：

• actionStart被調用，並且兩個日誌行打印是在分配給self.videoCamera.delegate
• imageView
• 的self對象是有效是有效的，並在屏幕上可見
• videoCamera當它的start方法被調用時被初始化

我使用iPhone 3GS進行測試。

這裏是我的ViewController.h的全部源：

#import <UIKit/UIKit.h> 
#import <opencv2/highgui/cap_ios.h> 

@interface ViewController : UIViewController <CvVideoCameraDelegate> 
{ 
    IBOutlet UIImageView* imageView; 
    IBOutlet UIButton* button; 

    CvVideoCamera* videoCamera; 
} 

- (IBAction)actionStart:(id)sender; 

@property (nonatomic, strong) CvVideoCamera* videoCamera; 

@end 

和ViewController.mm：

@implementation ViewController 

@synthesize videoCamera; 

- (void)viewDidLoad 
{ 
    [super viewDidLoad]; 

    self.videoCamera = [[CvVideoCamera alloc] initWithParentView:imageView]; 
    self.videoCamera.delegate = self; 

    self.videoCamera.defaultAVCaptureDevicePosition = AVCaptureDevicePositionFront; 
    self.videoCamera.defaultAVCaptureSessionPreset = AVCaptureSessionPreset352x288; 
    self.videoCamera.defaultAVCaptureVideoOrientation = AVCaptureVideoOrientationPortrait; 
    self.videoCamera.defaultFPS = 30; 
    self.videoCamera.grayscaleMode = NO; 

} 

#pragma mark - UI Actions 

- (IBAction)actionStart:(id)sender; 
{ 
    [self.videoCamera start]; 
    NSLog(@"video camera running: %d", [self.videoCamera running]); 
    NSLog(@"capture session loaded: %d", [self.videoCamera captureSessionLoaded]); 
} 

#pragma mark - Protocol CvVideoCameraDelegate 

- (void)processImage:(cv::Mat&)image 
{ 
    // Do some OpenCV stuff with the image 
    cv::Mat image_copy; 
    cvtColor(image, image_copy, CV_BGRA2BGR); 

    // invert image 
    bitwise_not(image_copy, image_copy); 
    cvtColor(image_copy, image, CV_BGR2BGRA); 
} 

@end 

Answer 1

我在iPhone 4測試，效果很好。也許iPhone 3GS沒有前置攝像頭？然後你必須改變這一行：self.videoCamera.defaultAVCaptureDevicePosition = AVCaptureDevicePositionFront到self.videoCamera.defaultAVCaptureDevicePosition = AVCaptureDevicePositionBack